The drop was due largely to natural field declines at several key fields with Cliff Head production down 15% from the previous quarter to 8035bbl of oil per day while Roc's share of production from the Zhao Dong block offshore China was 4661bpd, down 2% from the previous quarter.

Production from the Enoch and Blane fields in the North Sea were also down 13% and 1% respectively.

Roc said it is planning to carry out well workovers at Cliff Head to replace two electric submersible pumps with larger pumps which may improve well productivity.

The company also expects to start, in the second quarter of this year, a program of three well interventions and two new infill wells to increase production at the Chinguetti oil field offshore Mauritania.

In China, upgrade work on the offshore drilling and production platforms at the Zhao Dong C and D fields has been completed while a 12-well development drilling program was kicked off on March 20.

Roc plans to batch-drill five wells before completing and bringing them into production.

Work also continued on the construction and fabrication of facilities for development of the Zhao Dong C4 Oil Field with installation of the conductor pod completed ahead of schedule on March 26.

Also in China, Roc plans to submit an overall development plan for its Wei 12-8W and Wei 6-12 oil fields to the Chinese authorities in the middle of the year with a final investment decision expected in the second half of 2008.

Roc said the project has the potential to move unbooked discovered resources of 4.7-5.7 million barrels of oil into booked, proved and probable reserves.

Revenue for the quarter was up 16% to $US101.7 million ($A108.87 million) due to high oil prices and a 7% increase in sales volumes to 1.12MMbbl.

Banda appraisal looks good

Meanwhile, Roc has said the Banda NW ST-1 sidetrack appraisal well in Mauritania's PSC B permit has encountered oil and gas columns.

Contacts are similar to those seen in the discovery well, which was drilled in 2002 about 2km to the east. The well reached total depth of 2934m below the rotary table on April 28.

Roc has a 3.69% stake in the PSC Area B; PC Mauritania is operator with 53.84%, Tullow Oil 21.6%, and Mauritania Holdings BV 11.63%.